You know what I haven't been able to find with Google is data on average EPA MPG by state. I wanted to know the average (mean) MPG of vehicles sold by state so I could see if there is a correlation between fuel tax rate, and MPG.

As I've been saying, the correct way to reduce consumption of something which has negative externalities is to tax it to achieve consumption goals.

You know what I haven't been able to find with Google is data on average EPA MPG by state. I wanted to know the average (mean) MPG of vehicles sold by state so I could see if there is a correlation between fuel tax rate, and MPG.

As I've been saying, the correct way to reduce consumption of something which has negative externalities is to tax it to achieve consumption goals.

Back in January,1991,The Institute for International Economics,Washington,D.C.,figured that a 100% increase in the price of gasoline would net a 10% reduction in consumption.
Historically,it would be political suicide to sponsor this sort of legislation.
However,a December,2018 poll revealed that 81% of registered voters were in favor of the Green New Deal,so maybe,today,the noose would be made of thread,rather than rope.
I'd love to see the experiment.

Back in January,1991,The Institute for International Economics,Washington,D.C.,figured that a 100% increase in the price of gasoline would net a 10% reduction in consumption.
Historically,it would be political suicide to sponsor this sort of legislation.
However,a December,2018 poll revealed that 81% of registered voters were in favor of the Green New Deal,so maybe,today,the noose would be made of thread,rather than rope.
I'd love to see the experiment.

A 10% reduction in what timeframe though? I imagine if you doubled the price of gasoline overnight, you would only achieve a 10% reduction at best, because it didn't allow enough time to adjust, and the only savings would be in reduced trips and carpooling.

If the government published their very gradual tax rate schedule well in advance, consumers and industry would have time to adjust to progressively more expensive fuel.

The Green New Deal went nowhere in congress if I am informed correctly. There's no way it has 81% support anywhere, including wherever AOC is from. She probably doesn't even have 81% support from her own family.

Seems crazy that government agencies like the EPA are lead by POTUS appointees. Too much power I say.

If we disconnected executive office from government agencies, they would be free to set rules to achieve the goals which they are tasked with. Of course, it would take cooperation between agencies, since environmental agencies would not sufficiently consider economics, and vice versa. At least this way it isn't political suicide, since it wouldn't be a particular politician raising fuel taxes, but a governmental agency.

As a tangent, why does POTUS get to appoint supreme court justices for life? That job should be just like any other, where we either elect them, or they are internally promoted to the position.

A 10% reduction in what timeframe though? I imagine if you doubled the price of gasoline overnight, you would only achieve a 10% reduction at best, because it didn't allow enough time to adjust, and the only savings would be in reduced trips and carpooling.

If the government published their very gradual tax rate schedule well in advance, consumers and industry would have time to adjust to progressively more expensive fuel.

The Green New Deal went nowhere in congress if I am informed correctly. There's no way it has 81% support anywhere, including wherever AOC is from. She probably doesn't even have 81% support from her own family.

*The 100%/10% relationship wasn't unpacked in finer detail as to time frame.It could have been a mean average of polled individuals.Don't know.
That year,Congress passed a 6-cent federal gasoline/diesel tax increase.Absorbed without too much pain.
*The 81% figure comes from Yale University climate pollsters.Published in the May 6,2019,The Nation,page 18.Congress may not necessarily represent constituents.
I've never met AOC,I don't know anything about her.

Seems crazy that government agencies like the EPA are lead by POTUS appointees. Too much power I say.

If we disconnected executive office from government agencies, they would be free to set rules to achieve the goals which they are tasked with. Of course, it would take cooperation between agencies, since environmental agencies would not sufficiently consider economics, and vice versa. At least this way it isn't political suicide, since it wouldn't be a particular politician raising fuel taxes, but a governmental agency.

As a tangent, why does POTUS get to appoint supreme court justices for life? That job should be just like any other, where we either elect them, or they are internally promoted to the position.

The appointment issue might require a constitutional amendment,or a Supreme Court policy reversal.Whoops!
Policy has been pretty much ruled by economists since 1957,so they're probably already well represented.It's why we risk losing the planet.
They're more afraid of stranded investments than the loss of the biosphere.
There might be a case for the House and Senate being required to use a rigorous scientific metric in the confirmation process for POTUS nominees.It wouldn't matter how lame the president or their nominees were,Congress simply wouldn't be able to install the minion/sychophant/boot-lickers without an extreme portfolio of real qualifications.Not just whether or not they sexually molested someone when they were drunk.